Vitamin-mineral supplements do not guarantee the minimum recommendations and may imply risks of mercury poisoning in dogs and cats

Abstract

Given the importance of using the vitamin-mineral supplements to guarantee the minimum nutritional recommendations for pets in homemade foods, and hypothesizing that these products may contribute to toxic metals contamination, the present study aimed to determine the concentrations of essential minerals and toxic metals in vitamin-mineral supplements available in the Brazilian market and calculate if the amount recommended by the manufacturer guarantees the minimum recommendations of NRC (2006) and FEDIAF (2020), as well as calculating the amount of toxic metals that animals would consume, according to the amounts recommended by the manufacturer. Seven vitamin-mineral supplements were analyzed. The determination of essential minerals and toxic metals was performed using ICP-OES. Comparisons were made with the minimum recommendations for essential minerals, and with the maximum tolerated levels of toxic metals established by the FDA (2011), descriptively. Most of the vitamin-mineral supplements, in the quantities recommended by the manufacturers, do not guarantee the minimum recommendations of NCR (2006) and FEDIAF (2020) for the following elements: calcium, potassium, magnesium, sodium, phosphorus, selenium, and zinc. Only one supplement had detectable selenium concentrations. Three supplements provided more than 0.02mg of mercury/kg of body weight, the safe upper limit used to establish the maximum tolerated level of this element. It is concluded that most vitamin-mineral supplements do not meet the minimum recommendations for most essential minerals and, if formulated by untrained professionals, even with supplementation, homemade foods may still be nutritionally deficient. Furthermore, some vitamin-mineral supplements analyzed may imply risks of mercury poisoning in pets.

Mineral and heavy metal content in dry dog foods with different main animal components

“…Most vitamin and mineral supplements, in the amounts recommended by manufacturers, do not guarantee the minimum nutritional recommendations for the following elements: calcium, potassium, magnesium, sodium, phosphorus, selenium and zinc. In study by Zafalon et al 38 most vitamin and mineral supplements have been found to fall short of minimum recommendations for the most important minerals, and when formulated by untrained professionals, even with supplementation, homemade food may still be deficient in nutrients. Moreover, some analyzed vitamin and mineral supplements may suggest a risk of mercury poisoning in domestic animals 38 .…”

“…In study by Zafalon et al 38 most vitamin and mineral supplements have been found to fall short of minimum recommendations for the most important minerals, and when formulated by untrained professionals, even with supplementation, homemade food may still be deficient in nutrients. Moreover, some analyzed vitamin and mineral supplements may suggest a risk of mercury poisoning in domestic animals 38 . Our research did not detect the presence of Co, Cr, Ni.…”

“…In our study, the amounts of molybdenum found were relatively similar in all food groups (average 0.100-0.110 mg/100 g DM), but higher than those found by Pereira et al 16 (0.049 mg/100 g DM). In order to increase the proportion of minerals in the diet, vitamin-mineral supplements 38 can be used, which is common practice among dog caregivers on a home or raw diet. Most vitamin and mineral supplements, in the amounts recommended by manufacturers, do not guarantee the minimum nutritional recommendations for the following elements: calcium, potassium, magnesium, sodium, phosphorus, selenium and zinc.…”